Gecko Feet

This post is for those who don't know much about biomimcry or the inventions it has lead to. One of the most popular and modern examples of biomimetics are artificial adhesives inspired by gecko feet.

We all know that geckos can cling to walls and scurry across ceilings with ease, but did you ever wonder how they did this? The secret to the geckos amazing sticking abilities lie in the billions of hair-like structures that adorn their toes.

As you can see, the toes bare a series of ridges which are covered by the hair-like setae. Each setae is further divided into hundreds of split ends called spatulas. These are very important because these setae allow very small intermolecular forces called Van der Waals forces to provide the adhesion the geckos need.  Each square millimeter of a gecko's foot has about 14,000 setae. This means that the setae of an average adult gecko weighing 70 g (2.5 oz) can support a aweight of 133 kg (293 lb).

Scientists have been studying these structures for some time and in the last ten years or so have been able to create synthetic setae. As of now, many of the techniques consist etching a polymer with electrons to create the very small setae.

Using these techniques, engineers have created a few products that take advantage of the gecko's amazing adhesive abilities. One of these is "Gecko Tape." It was about 1cm² large and and could hold more than 100g (3.5 oz).

Micro View of Gecko Tape

A similar product is called "Geckel" and is very similar to Gecko Tape but instead of relying exclusively on dry adhesion, it also depends on chemical reactions of a glue derived from mussels in order to increase adhesion under wet conditions.